Flock-applying apparatus



April 23, 1968 F, 'r, SPENCER 3,379,175

FLOCK-APPLYING APPARATUS Filed April 8. 1966 Ja e/5Z0) Ira/was .gwwa r122" a United States Patent 3,379,175 FLQCK-APPLYENG APPARATUS FrancisT. Spencer, Biddeford, Maine, assignor to West Point-Peppercii, lino,iioston, Mass, a corporation of Georgia Filed Apr. 8, 1966, er. No.541,321 6 Claims. (Cl. 118636) ABSTRACT 0F THE DISCLOSURE Anelectrostatic grid structure interposed in the path of downwardlyfailing flock fibers dropped freely from a dispensing device, said gridstructure comprising parallel, spaced rotatable elements charged to ahigh electrostatic potential, and means for rotating said cylindricalelements at a constant predetermined angular velocity.

This invention pertains to apparatus for applying flock fibers to anadhesively-coated surface-more particularly to apparatus of the kindwherein the flock fibers, in tip proaching said surface, are caused tofall freely through an electrostatic field whereby the fibers tend toarrange themselves in parallel relation.

In the cop-ending application for Letters Patent, Ser. No. 494,691,filed Oct. 11, 1965 by Francis T. Spencer, there is disclosed a soft,drapeable material comprising a reinforced ply of foam plastic having anadherent layer of flock of a character and so applied as, for example,to simulate the nap produced by napping woolen fabric or even to havethe appearance of natural fur. Flock fibers of a denier of from 3 to 6and of a length of from 2 to 6 mm. are suggested as useful in makingsuch material.

In accordance with the procedure described in the aforesaid application,the flock fibers are deposited in spaced relation, that is they arerelatively sparse as compared with usual procedure, and in order to getthe desired results, for example, heat insulation; pleasing appearance;or ornamental effects, these fibers should be predominantl perpendicularto the base fabric and arranged with substantially uniform distributionso that the completed material provides a substantially uniformly levelsurface defined by the tips of the fibers.

In accordance with customary prior practice, the flock fibers aredischarged from a hopper by gravity and, in dropping, pass through anelectrostatic field which has the purpose of orienting the fallingfibers so that they become substantially parallel as they continue tofall and eventually drop into contact with the adhesively-coated surfaceof the base fabric which is being rapidly vibrated up and down by beaterdevices disposed below it. T e electrostatic field is usually producedby the use of a grid comprising stationary steel tubes of the order ofof an inch in diameter spaced a short distance apart and which arecharged to a very high potential by appropriate electrical apparatus.The lines of force first extend outwardly from these bars in a generallyradial direction but then bend downwardly toward the earth.

While the customary flocking apparatus, such as above briefiy outlined,is reasonably satisfactory, when applying the short flock fibers,particularly those of a coarse denier, it has been found, inmanufacturing material of the general type of that described in theaforesaid application and in the practice of which flock fibers of lowdenier, for example, but without limitation, not substantially exceeding8, and of a length of 2 mm. or more, there is a tendency for these longand fine flock fibers gradually to build upon the grid bars, especiallyupon the upper portion of the grid bar. This is due, apparently to thefact that the lines of force which emanate from the grid bars tendpredominantly to curve downwardly away from the grid bars so thatdirectly above each grid bar there is a space within which the forcesacting upon such a long and fine fiber, which has settled down onto thebar, are not such as to detach the fiber from the bar. Eventually, whena mass of fibers has been built up to a certain size, the mass falls offfrom the grid barusually breaking up into small balls which, as theycontact the upwardly and downwardly vibrating base fabric, are tossed upand down repeatedly, and these small balls of dense flock fibers, indropping back onto the upstanding flock fibers which are just about toadhere to the base fabric, form peck-marks or depressions in the flocklayer which spoil the desired smooth appearance. Thus, it is necessaryto stop the machine at frequent intervals and clean off the flock byhand from the grid bars.

The object of the present invention is to provide apparatus for applyinglow denier flock, for instance, from 3 to 6, and, for example, of theorder of 2 mm. or more in length, in the manufacture of flocked fabric,whereby the above difficulties are overcome, and to produce a deep flocklayer devoid of irregularly distributed cavities or fortuitously locatedareas wherein the fibers are nonparallel or abnormally dense, or are notperpendicular to the base fabric. In the attainment of this object, inaccord ance with the present invention, the grid bars, whereby theelectrostatic field is produced, and which in prior devices arestationary, are so mounted that they may be rotated at a s eed which mayvary in accordance with the character of the fibers, but which may bewithin a range, for example, of from 5 to 30 rpm. With such anarrangement the build up of fibers on the grid bars is completelyprevented with the result that the final product is no longer damaged bythe droppin and bouncing of masses of material falling from the gridbars.

In the drawings:

FIG. 1 is a fragmentary front elevation illustrating one desirableembodiment of the invention;

FIG. 2 is a fragmentary section, to larger scale, on the line 22 of FIG.1, showing one of the rotary electrodes, in accordance with the presentinvention, whereby the building up of fiber masses on the electrode isprevented; and

FIG. 3 is a fragmentary diagrammatic vertical section illustrating amodified construction of grid bar.

Referring to the drawings, the character F designates a portion of themachine frame which supports bearings for parallel, horizontal, rotaryshafts 10 and 10a, each of which has fixed thereto a drum D. These drumssupport an endless belt B having a horizontal upper run which contacts atable T of electrical-conducting material, and which carries the basefabric K. (FIG. 2) which, in accordance with customary practice, willhave an adhesive upper surface onto which flock fibers S drop afterfalling through the electrostatic field. The shaft 10 is provided with asprocket which receives a chain C which is driven continuously by anelectric motor M through the intermediary of a variable-speed,speed-reducer R. Above the endless belt, suitably supported hoppers 11,11a are arranged to discharge flock so that it will fall through theelectrostatic field onto the surface of the fabric S. Theseflock-distributing hoppers may be of customary type, each having a shaft12 or 12a, respectively, carrying agitating means of any desired type(not shown) driven by the motor M through suitable connections A andhaving slots in their lower portions through which the flock isdischarged.

An auxiliary frame 13, below the hoppers, supports hangers 14 and 15 ofinsulating material, desirably having bearings 16 (FIG. 2) of nylonwhich receive trunnions 1'5, which may also be of nylon, fixed in plugsP secured in the opposite ends, respectively, of tubular bar-elecetrodes E. It will be understood that, if desired, each grid bar may bemounted upon a shaft extending through it, from one end to the other,rather than on trunnions.

As here shown (FIG. 2) the trunnion 15a which extends outwardly from therear end of the electrode E is provided with a sprocket which isembraced by a chain 17 which also embraces a sprocket 18 on the rear endof the shaft 10a which carries the drum D. By this means the electrode Eis constantly rotated. A sprocket 26, also fixed to the trunnion 15a, isembraced by a chain 21 which also embraces a sprocket on the trunnion atthe forward end of the next electrode E (FIG. 1). In a similar way, theelectrodes E and E are driven. Since the apparatus may be, in general,similar to those in customary use, except that customarily theelectrodes are stationary, it appears unnecessary to describe themechanism and electrical connections in further detail-it beingunderstood that, for example, the electrodes or grid bars will becharged to one polarity, for example positive, while the support for thematerial to which the fibers are to be I applied will be charged to theopposite polarity, for example negativethe charge being established andmaintained by any suitable or conventional apparatus such asdiagrammatically indicated at T (FIG. 1). While the desired arrangementfor rotatably supporting the grid bars or electrodes by the use ofelectrically insulating material is desirable, it will be understoodthat equivalent means is contemplated as within the scope of theinvention.

To avoid difiiculties which might be experienced in so supporting arotating grid bar as to prevent leakage of the charge, a modifiedarrangement, as illustrated in FIG. 3, shows the grid bar E asstationary, being supported at its opposite ends in frame elements 14aof insulating material with a suitable conductor W connected to the barnear one end and through which the charge is supplied to the bar. Inthis instance, the bar E or at least that portion of which functions forthe purpose of the present invention, is housed within a non-conducting,rotary, hollow guard cylinder G having hollow trunnions T at itsopposite ends, through which the ends of the grid bars pass, and whichare received in hearings in stationary frame members Z which, desirably,should also be of insulating material, one of the trunnions T havingfixed thereto a sprocket wheel W which is embraced by a chain 17a, likethe chain 17 of FIG. 2, by means of which the guard cylinder is slowlyrotated. With this arrangement, using a cylinder of non-conductingmaterial, the lines of force emanating from the bar E pass outwardlythrough the walls of the guard cylinder G so as to provide thefunctional effect of the usual stationary grid bars. However, since thecylinder G is slowly rotating, any tendency of the flock fibers, as theyfall downwardly between the grid bars, to build up on the upper part ofthe cylinder G is nullified by the rotation of the cylinder and thus thesame beneficial efiects are obtained as by the arrangement shown inFIGS. 1 and 2.

While reference has hereinabove been made to the use of the apparatusfor making flocked material having a deep flock layer, desirable forheat-insulation; or to simulate napped woolen material or natural fur,it is to be understood that the apparatus herein described is likewiseuseful in applying flock of any length or denier, and in the manufactureof such articles or fabrics as hosiery, draperies, blanket bindings,artificial furs, bed blankets, childrens bed-clothing, etc., or forpurely ornamental effects.

It is also to be understood that the apparatus as illustrated andhereinabove described is by way of example and that the invention isbroadly inclusive of all modifications and means, for preventingbuild-up of fibers on the grid bars, which fall within the terms of theappended claims.

I claim:

1. In combination, in apparatus for applying flock fibers of a denierwithin a range of from 3 to 6 and of a 4 length not substantially lessthan 2 mm. to an adhesivelycoated base, a container for flock. fibershaving a discharge aperture through which fibers may fall, a grid,

electrically charged to one polarity and comprising spaced bars solocated below the container that flock fibers, falling from thecontainer, pass between said bars, an element charged to the oppositepolarity for supporting the base to which the flock. is to be adhered;characterized in having means for rotatably supporting the individualbars of the grid, and means for rotating said bars at such a speed as toprevent the build-up of flock fibers upon said bars.

2. In combination, in apparatus for applying flock fiber of a denier notsubstantially exceeding 8 and of a length exceeding 2 mm. to anadhesively-coated surface and which comprises means for supporting saidsurface, an electrostatic grid above said surface whose electrical potential is opposite to that of said surface, and means above said gridfor so discharging flock fibers that the fibers fall between the bars ofthe grid and onto said surface; characterized in that the grid comprisesa plurality of spaced parallel bars, means for supporting the individualbars to rotate, and means for rotating the several bars.

3. Apparatus according to claim 2, wherein each grid bar is cylindricaland tubular, insulating means supporting each respective bar, and motormeans for rotating each of said bars.

4. Apparatus according to claim 1, and wherein the flock container hastherein an agitator operative to stir the flock fibers within thecontainer and to discharge fibers from the container, and wherein eachof the grid bars comprises a hollow cylinder, means for supporting eachcylinder to rotate about its own axis, the supporting means being suchthat the cylinder is insulated from the earth, an

" electric motor, and means for transmitting motion from the motor foractuating the flock agitator in the hopper and for rotating each of saidhollow cylinders.

5. In combination, in apparatus for applying flock fibers to anadhesively-coated base, a container for flock fibers having a dischargeaperture through which fibers may fall, a grid, electrically charged toone polarity and comprising spaced parallel cylindrical elements solocated below the container that flock fibers, falling from thecontainer, pass between said elements of the grid, and an elementcharged in the opposite polarity for supporting the base to which thefibers are to be adhered, characterized in that said cylindricalelements are hollow and rotatable, and power-operable means for rotatingsaid cylindrical elements at a predetermined angular velocity,

6. In combination, in apparatus for applying flock fibers to anadhesively-coated base, a container for flock fibers having a dischargeaperture through which fibers may fall, a grid, electrically charged toone polarity and comprising spaced parallel cylindrical elements solocated below the container that fibers formed .on the container passbetween said elements, further characterized in that said cylindricalelements are hollow and are of a nonconducting material, each of saidelements housing a fixed grid bar of conductive material, meansinsulating each of said fixed bars from the earth, further characterizedin having power-operated means for turning said rotatable cylindricalelements at a predetermined uniform angular velocity thereby to preventthe build up of flock fibers upon said cylindrical surface.

References Cited UNITED STATES PATENTS 2,245,301 6/1941 Schacht 118638 X2,715,585 8/1955 Schwartz et a1 1l8-636 X 2,742,018 4/ 1956 Lindquist118-636 3,114,482 12/1963 Dunaway.

3,269,356 8/1966 Friderici 118640 CHARLES A. WILLMUTH,Prima1y Examiner.

PETER FELDMAN, Examiucn

